Propulsion of ships



(No Model.) V v J. B. ROOT.

' INVENTOR ATTORNEY N. PETERS. Phaxoulho n hen wmhingmn, D, (L

V UNITED S TE PATENT OFFICE.

JOHN-B. ROOT, OF PORT CHESTER, NEW YORK.

PROPULSION OF SHIPS.

SPECIFICATION forming part of Letters Patent No. 253,946, dated February21, 1882.

Application filed December 6,1881. (No model.)

'method of applying screw-propellers to the stems of vessels; also, toobviate the necessity oflon g screw-shafts and their liability to break5 also, to provide a way of applying the propelling power to vessels bytwo or more independ ent engines, thus reducing the risk of disablementof vessels by accidents to their engines.

The invention consists in the combination,

in a vessel, of a screw or equivalent device arranged to move 'the watertransversely to the line of movement of the vessel and an inclinedpropelling-surface of the hull for receiving the increase or decrease ofpressure produced by the transverse movement of the water, such surfacebeing inclined to or at an angle with the fore-and-aft line or line ofmovement of the 2 5 vessel, whereby the vessel will be propelled in onedirection by throwing the water against such inclined surface and in theopposite direction by drawing the water away from suchinclined surface;also, in a screw or screws working upon a shaft or axis placed substantially at right angles to the line of movement of the vessel andconstructed to move the water transversely to the line of movement ofthe vessel, in combination with an inclined propelling-surface of thehull for receiving the increase or decrease of pressure produced by thetransverse movement of the water, such surface being inclined to or atan angle with the foreand-aft line or line of movement of the vessel,whereby the vessel will be propelled in one direction by throwing thewater against such inclined surface and in the opposite direction bydrawing the water away from such inclined surface, all substantially ashereinafter described and claimed.

The invention is illustrated in the accompanying drawings, in whichFigure 1 is a side elevation of a vessel containing my improvement, thescrews being entirely submerged at one end of the vessel and onlypartially submerged at the other end. Fig. 2 is a plan view of the same,and Fig. 3 illustrates an application of my improvement to the bow orstern of a vessel.

By reference to the drawings the application and operation of myimprovement is described as follows:

In Figs. 1 and 2, A and B represent two pairs of screws, the screws ofeach pair being connected by their respective shafts or axes a and 1),extending across the vessel and provided with cranks c and d, to whichthe power is applied. The pitch of the screws A and B upon the one sideof the vessel is opposite or opposed to their pitch upon the other sideof the vessel-that is, their pitch is so arranged that the'screws actingupon one side of the vessel will throw or propel the water in adifferent and opposite direction from that in which the screws actingupon the opposite side of the vessel will throw it, and the water passedthrough the screws will be moved or propelled transversely to the lineof the movement of the vessel. If the screws B are revolved so as tothrow the water passed through them away from the vessel, the vesselwould move to the right, as looked at in the drawings, this movementbeing caused by the diminishment of the pressure of the water upon theinclined sur faces of the hull adjacent to the screws B.- If

the screws B are revolved in the opposite direction, so as to throw thewater passed through them against the inclined surfaces of the hull, themovement of the vessel would be to the left, as looked at in thedrawings, this movement being caused by the impingement of the waterpassed through the screws against the inclined surfaces of the hull,thus increasing the pressure upon the inclined-wedge shaped portion ofthe hull adjacent to thescrews. If both pairs of screws A and B work inunison,'so that one pair diminishes the pressure against inclinedsurfaces at the forward end of the hull and the other pair increases thepressure against inclined surfaces at the after end, the vessel willmove forward with a speed due to the power applied.

Fig. 3 shows a way of applying the same principle to the bottom of avessel at either the bow or stern, or both, with a screw or screwshaving vertical axes, U representing the screw and 2 its shaft or axis.In this application the movement of the water will be verticallytransverse to the line of movement of the vessel that is, the water willbe moved upward or downward, instead of horizontally transverse, as isthe case when the shaft or axis is horizontal, as shown in Figs. 1 and2.

It is evident that the axes of screws may be applied at any anglebetween the vertical and horizontal positionsshown in the drawings, itbeing essential that the pitch of the screws and their arrangement ontheir shafts be such as to move the water transversely to the line ofmovement of the vessel, and that the arrangement of the screws and theinclined surfaces of the hull be so related to each other that theincrease of pressure of the water shall be against the inclined surfaceswhich converge toward the fore-and-aft line of the vessel at the endopposite the direction in which she is moving, and the decrease ofpressure of the water shallbe against the inclined surfaces whichconverge toward the fore-and-aft line at the end of the vessel whichpoints in the direction of her movement.

From the above description it is seen that the inclined surfaces of thehull of the vessel when acted upon by the water thrown against or drawnaway from them by the transverse action of the screw or equivalentdevice become the propelling-surfaces, or means by which, in conjunctionwith the screw,the vessel is moved either forward or backward. Thetransverse action of the screw alone has no tendency to move the vesselin either of the directions named.

Although Ihave only shown in the drawings screws arranged upon shafts oraxes substantially at right angles to the line of movement of the vesselas the preferable construction, I donot limit myself to such precisearrangement of the shafts, as it is evident that the position of theshafts can be considerably varied from that shown, and substantially thesame results produced, by varying the angle of the propelling-surfacesof the bull or thepitch of the blades of the screw, or both; neither doI confine myself to the use of screws for throwing the water against ordrawing it awayfrom the inclined propelling surfaces, as it is evidentthat other equivalent devices may be used for this purpose-as, forinstance, sculling blades or paddles so constructed and arranged as tothrow the water against or draw it away from such propelling-surfaces.

Itis evident that with the arrangement above described long screw-shaftscan be dispensed with, and that each screw or pair of screws may bedriven from a separate engine. By partially submerging the screws, asshown at A in Fig. 1, and giving them sufficient diameter, the frictionof the blades in the water may be, in great part, converted intopropelling force; also, the shaft may be brought above the water-lineand made more accessible. This form of side screw is well adapted toshoal water. It isimportantthat the wed ge-like ends of the hull shouldbe of such form as to best utilize the impact of the water. A hollowcurve gradually approaching the center fore-and-aft line of the vesselis the best; also, the ends of the'hull should extend far enough beyondthe screws to insure the full effect upon the hull of the momentum ofthe water putin motion by the screws.

This method of screw propulsion is particularly adapted for applicationto canal-boats.

What is claimed as new is- 1. In a vessel, a screw or other equivalentdevice arranged to move the water transversely to the line of movementof the vessel, in combination with an inclined propelling-surface of Athe hull for receiving the increase or decrease of pressure produced bythe transverse movement of the water, such surface being inclined to orat an angle with the fore-and-aft line or line ofmovem ent of thevessel, whereby the vessel will be propelled in one direction bythrowing the water transversely against such inclined surface and willbe propelled in the opposite direction by drawing the water away fromsuch inclinedsurface, substantially as described.

2. In a screw propeller, a screw or screws working upon a shaft or axisplaced at substantially right angles to the line of movementof'thevessel and constructed to move the wa-,

ter transversely to such'line of movement, in

combination with an inclined propelling-surface of the hull forreceivingthe increase or decrease of pressure produced by the transverse movementof the water, such surface being inclined toor at an angle with theforc-and-afa line, or theline of'movement of the vessel, whereby .thevessel willbe propelled in one direction by throwing the watertransversely against such inclined surface and in the opposite directionby drawing the water away from such 1nclined surface, substantially asdescribed.

JOHN B. ROOT.

Witnesses:

R0131. H. DUNCAN, W. F. HAPGOOD.

